Cement gun apparatus



Ot. 2, 1951 1. M. RIDLEY CEMENT GUN APPARATUS Filed July 27, 1948INVENTOR: IAN M. P/DLEY BY a A TTOR/VEKS.

Patented Oct. 2, 1951 UNITED STATES PATENT OFFICE 2,569,952 CEMENTGUNAPPARATUS Ian M. Ridley, Burbank, Calif.

Application J uly. 27, 1948, Serial No. 40,922

4 Claims. "(CL 91 44) This invention relates to cement gun sandblastingequipment and the like, and more particularly to a new and improvedsandblasting or cement gun apparatus of improved overall and meteringconstruction.

Prior art devices must ordinarily be shut down while they are rechargedwith raw materials, such as cement or sand or both. Their operationisconsequently intermittent. Presently known apparatus also tends todeliver sand or mixtures of sand and cement with an uneven, irregularand often spasmodic flow so that the size of the apparatus is ordinarilyexcessive for the purposes for which the instant apparatus is intended,and the supply of material to the delivery nozzle and place ofapplication is relatively excessive because of the absence of asatisfactory metering device.

v Prior art apparatus is also subject to excessive wear in use and theworking parts are replaceable only with difficulty.

. Therefore an object of this invention is. to avoid the aboveobiections and to provide an apparatus usable either as an, applicatorfor a mixture of cement and sand or as a sandblasting unit which neednot be shut down while in use, which may be readily made from availablema terials, which affords easy access to all of its working parts forreplacement or repair, and which provides a steady controllable andcontinuous supply of preferably dry mixed cement and sand as desired.

It is another object of this invention to provide a tank type cement gunapparatus which is usable as a sandblaster, all parts of which may bepowered by a single compressed air source and having anoverallsimplicity of construction.

It is another object of this invention toelimie nate customary gears andother complicated mechanism for performing the desired function.

Another more specific object of. the invention is the provision of animproved metering means associated with a new and improved meteringorifice whether considered either alone or .in the cited combination.

Another further object of the invention is the provision of a meteringapparatus bearing a unique and satisfactory relationship to the feedchamber with Which it is' associated.

It is moreover an object of this invention to provide improvements overprior art devices generally intended to be put to a similar use.

With these and other objects in view, the invention consists in theconstruction, arrangement and combination of the various parts of thedevice whereby the objects contemplated are attained, as hereinafter setforth, pointed out in the appended claims and illustratedjin theaccompanying drawings.

2 In the drawings: Figure 1 is a vertical sectional view, parts beingcut away of an apparatus illustrative of this i I invention.

Figure 2 is a vertical sectional view as on a line '2-2 of Figure 1.

Figure 3 is a detailed enlarged View of the metering mechanism.

Figure 4 is a detailed view of a modified form of metering orifice.

Referring more particularly to the drawings, an'apparatus embodying thisinvention by way of illustration and not of limitation comprises a tankl divided into an upper compartment 5 i and a lower compartment 12.These compartments may be respectively fitted as with hemispherical cups[3 and 14, respectively, comprising check valves, the upper one l3ofwhich, at least,

I may be raised or lowered by means of a Windlass type construction suchas a handle l5 or automatically by compressed air as will be seen. Theturning of the handle 15 may lower the hemispheres from the positionsillustrated in Figure 1 by straightening the toggle links l1, l8, of thevalve 13, or if desired, of the valve l4 as Well. The lower link l8 maybe provided with a ball set in a suitable socket IQ for universalmovement.

The upper compartment H is defined by a top transverse wall 2|,optionally funnel-shaped in the 'manner of a hopper, and a preferablyfunnel-shaped lower wall 22 which incidentally also comprises the top ofthe chamber l2. Orifices 24 and 25 associated with the hemispheres l3and 14 are provided with packing rings 26 or the like to insure anair-tight closure of the hemispheres thereagainst.

A tube 23 and rod 29 project downwardly, most desirably, at an anglethrough the walls 2| and 22 so as to clear the openings 24 and 25, toprovide outside mounting for the driving means as will be seen, and tofacilitate acquisition of a desired angle for the metering means as willalso be set forth hereinafter. The rod 29 extending therethrough isaccommodated by ported caps to at the ends of the tube 28, and the tubeis made air-tight in its passage through the tank as by suitable ringpacking 21.

An air motor or the like 32 is operatively connected to the rod 29 tocause the rotation thereof, whereby the agitator arms or stirrers 33welded to the rod 29 are caused to rotate and mix dry cement and sand 35disposed in suit able proportions within the tank H3. The tube 28 mayhave either packing or bearings 36 for ribbon 3! extending into apreferably threaded I nipple 38, a sleeve 39, and another nipple 48formed with a tapered shoulder 4I providing a constricted tubular-shapedorifice 42.

.A notch 43 formed in the lower end of the ribbon 3'! thereby formswings 48 which, upon rotation of the rod 29 and the ribbon 31,optionally secured thereto in a releasable manner as by a keyed orrecessed hub 49 and set screw arrangement, assist the screwing action ofthe ribbon 37 in metering a dry sand or cement and sand mixture 35through the orifice 42.

A stirrer 33 may be welded or reverse threaded as by means of a sleeveor the like (not shown) to the hub 49.

The nipple 48 may be formed integrally with the shoulder portion 4| orseparately therefrom as a removable insert as within the sleeve 39. Saidnipple 40 is threaded into a T 5| across the run of which a pipe 52leading from an air supply (not shown) is passed. A boss 53 maybethreaded into a suitable reinforcing shoulder 56 at the bottom of thetank III in order to support the last mentioned mechanism in a preferredangular position as shown.

An outlet control valve 60 is openly connected with the upper chamber IIand an inlet control valve SI interconnected with the air supply pipe52, preferably after the passage of the latter through a pressurereduction valve 62, controls the flow of air from the supply pipe 52 tothe upper, chamber II. V

The apparatus above described may be placed on wheels, skids, or thelike for mobility, or may be provided with a supporting framework suchas legs 65 to support the same in a verwhich may be lowered from itsclosed raised position by rotation of the handle I5, optionally also, orin addition, opening the outlet valve 60 any air under pressure withinthe upper chamber II will be exhausted to the atmosphere, the inletvalve BI meanwhile having been closed in either case.

When the upper chamber II has been filled with entrant raw materials toa sufficient extent the valve 60 is closed and the valve 6 I then openedpermitting air under pressure to enter the chamber II and forcing thehemisphere I3 closed. Compressed air from its source in passing throughthe pressure regulator valve 52 bypasses the inlet valve BI and entersthe lower chamber I2 by pipe 63, whereby a constant pressure ismaintained within said lower chamber normally equal to that within theupper chamber I I when the inlet valve GI is open. Thereby, the weightof an entrant dry sand and cement mixture above and upon the hemisphereI4 causes a pressure differential which ticalposition as shown. In anyevent an air supply hose separate from the supply pipe 52 may bedirectly connected to the compressor or other air source (not shown) foroperating the motor 32 which may likewise be provided with a regulatingmechanism. of conventional construction to control the speed thereof.connection 66 may be continuous with the run of the T 5| and lead to adelivery nozzle 61 also of conventional construction. An auxiliary airsupply hose 68 or the nozzle 51 may connect with the compressor sourceor the delivery hose 65, and another hose 69 may be connected to a watersource to convey air and water, respectively, under pressure to thedelivery nozzle 67 in order to disperse and throw the dry sand mixturefrom the T 5|, optionally a venturi, and to spray the same with watervapor, to moisten the same to a desired extent so that it may adhere toa surface upon which it is directed. The apparatus is used forsandblasting. Manifestly the pressure reduction valve 62 may beeliminated or opened to its fullest extent, and the air and auxiliarywater hoses 68 and 69 leading to the nozzle may be turned off orremoved.

Y The handle I5 for controlling the upper hemisphere I3 for example mayhave a horizontal rod 82 extending therethrough provided with a sleevebushing 83 with a cap 84 and rubber gasket 85 therein to make the sameair-tight and also provided with a cup bushing 86 at its opposite end.vThe links otherwise connected to the rod 82.

Operation I! preferably are welded or A hose automatically opens saidvalve I4 and permits the dry mixture to fall into the chamber I2 as thelatter is exhausted, i. e., it may be noted that due to its weight thehemisphere I4 may remain open even when pressures within the chambers II and I2 are equal as when the outlet valve 60 is closed and the inletvalve BI is opened.

However, upon the opening of the valve 60 and closing of the valve BIthe air pressure within the lower chamber I2 exceeds that within theupper chamber I I forcing a closing movement of the hemisphere I4.Valves I0 and 'II in the supply pipe 52 control the flow of air to thelower chamber I2 and the nozzle 61.

During the normal operation of the apparatus, the passage of air fromthe source, through the pipes 52, through the T '5I, and thence into thenozzle 61, carries with it the sand and cement mixture as it is meteredthrough the orifice 42. In the nozzle 61, the preferably, though notnecessarily, dry mixture 35 prior to its ejection from the tank 66 iswetted, as stated, with a spray of desired density formed by theinjection of water or air and water under pressures of approximately 60and 80 pounds respectively, thereby 48 preferably conform to thecorresponding surface of the shoulder H and may be either slidablethereon or only placed in proximity thereto.

The notching 43 of the lower end of the screwlike ribbon 31 provides anappropriate outlet for the bulk of material contained within theenlarged sleeve portion 39. In combination with said slot and saidinterior of the sleeve 39 the fingers 48 in their revolving movement donot jam but provide a free stirring movement for the granular orpowdered material thereabove. An evenness of flow is thereby obtained ofsaid material which drops through the orifice 42 and into the TM wherethe same is picked up by the air stream passing through the supply pipe52 to the left as illustrated in the drawings. In view of the granularnature of the material used the pressure of the air within the lowerchamber I2 passes in part through the material because of said porousnature and assists in the transmittal of the same through the nipple 38and'the sleeve 39.

comprising the nipple 38 and sleeve 39 further Moreover the amount ofextension of the twisted ribbon 31 into the upper orifice portionregulates and controls the flow through the restricted portion of theorifice 42.

As illustrated in Figure 3 said orifice 42 is shown to have substantialvertical depth from the bottom of its top tapered edge to the top of itslower tapered edge, but the same may be reduced to a relatively thinline I3 as illustrated most clearly in Figure 4, wherein othercorresponding parts are designated by like numerals to those illustratedin Figures 1, 2 and 3. The orifice 13 per se is therefore shown as beingwithout substantial cylindrical wall portions similar to those 42 ofFigure 3.

Rotation of the screw 3'! against the shoulder 4| may be achieved ineither embodiment in order to retain a proper working condition of theseparts to maintain a sharp line of contact therebetween and to preventsticking by entrance of powdered or granular material between theadjacent sliding surfaces.

The construction of this apparatus is such that may be readilydismantled and any or all of the parts removed for replacement orrepair. The notch 43 may thereby be enlarged or reshaped as needed andthe length of the screw 31 may be regulated by suitable telescopicadjustment in the keyed relationship of the hub 49 and the shaft 29 toprovide relative axial movement or provision for adjustment.

This invention features the provision of a convenient uniformlyoperating sandblasting and/or cement spraying apparatus of outstandingperformance. A satisfactory size has been found to be an approximate 40"height for the tank and an'approximate 18" diameter therefor, theopenings 24 and 25 being preferably approximately 4" in diameter, andthe angle of slant of the transverse portion 22 and bottom 80approximately 45. The agitator 33 may be shaped to conform to suchbottom portion 80 along the most proximate wall thereto. The rod 29 andscrew 37 may, if desired, although this is not the preferredconstruction, be given a vertical position to the other parts. A slightclearance between the lower end of the twisted ribbon 31 and shoulder 4|has also been found desirable with certain types of granular andpowdered material.

While I have herein shown and described my invention in what I haveconceived to be the most practical and preferred embodiment, it isrecog-- nized that departures may be made therefrom within the scope ofmy invention, which is not to be limited to the details disclosed hereinbut is to be accorded the full scope of the claims so as to embrace anyand all equivalent devices.

The invention having been herein described, what I claim as new anddesire to secure by Letters Patent is:

1. In a cement gun apparatus comprising a hopper for dry sand and/orcement, a substantially vertical outlet formed at the bottom of thehopper, metering means rotatable on a substantially vertical axis inalignment with andabove said outlet, drive means for rotating saidmetering means. a source of compressed air, a delivery means fordischarging said dry material from a station below said outlet to apoint of use by means of said air, said metering means comprising avertical screw-shaped ribbon, said outlet being formed with a seatthereabove, said ribbon having a bifurcate lower end portion straddlingsaid outlet, the lower ends of the biiurcate portion being slidablerotatively upon said seat, and means for rotating said ribbon.

2. In a cement gun apparatus comprising a hopper for dry sand and/orcement, a substantially vertical outlet formed at the bottom of thehopper, metering means rotatable on a substantially vertical axis inalignment with and above said outlet, drive means for rotatin saidmetering means, a source of compressed air, a delivery means fordischarging said dry material from a station below said outlet to apoint of use by means of said air, said metering means comprising avertical screw-twisted ribbon, said outlet being formed with a seatthereabove, said ribbon having a bifurcate lower end portion straddlingsaid outlet, the lower ends of the bifurcate portion being slidablerotatively upon said seat, and means for rotating said ribbon.

3. In a cement gun apparatus comprising a hopper for dry sand and/orcement, a substantially vertical outlet formed at the bottom of thehopper, metering means rotatable on a substantially vertical axis inalignment with and above said outlet, drive means for rotating saidmetering means, a source of compressed air, a delivery means fordischarging said dry material from a station below said outlet to apoint of use by means of said air, said metering means comprising avertical screw-shaped ribbon, said outlet being formed with an annularrestricted shoulder having a tapered seat, said ribbon having abifurcate lower end portion straddling said outlet, the ends of thebifurcate portion being tapered to correspond with the taper of the seatand to make line contact therewith on each side thereof and beingrotatably slidable thereon, and means for rotating said ribbon.

4. In a cement gun apparatus comprising a hopper for dry sand and/orcement, a substantially vertical outlet formed at the bottom of thehopper, meterin means rotatable on a substantially vertical axis inalignment with and above said outlet, drive means for rotating saidmetering means, a source of compressed air, a delivery means fordischarging said dry material from a station below said outlet to apoint of use by means of said air, said metering means comprising avertical driving member, said outlet being formed with a seatthereabove, defining a central opening, said vertical driving memberhaving opposed horizontally spaced finger-like stirring elementsdepending therefrom and straddling said outlet, the lower ends of saidfingerlike elements each moving around said seat, said finger-likestirring elements defining a space between them and above the opening insaid seat, and means for rotating said driving member.

IAN M. RIDLEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 699,405 Newhouse May 6, 1902998,762 Faller July 25, 1911 1,047,680 Mills et al Dec. 17, 19121,333,079 Kaufmann Mar. 9, 1920 1,559,666 Bernier Nov. 3, 1925 1,718,507Wenzel et al June 25, 1929 1,737,044 Conley Nov. 26, 1929 1,954,005Westberg et a1 Apr. 10, 1934 2,006,757 Bostrom July 2, 1935

